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Case Studies in Surgery
2016, Vol. 2, No. 2
CASE REPORTS
Case report of an isolated fracture of the anatomic
neck of the scapula
Drew P Kelly∗, Zachary V Roberts
The University of Oklahoma Health Sciences Center, Department of Orthopedic Surgery & Rehabilitation, Oklahoma City,
United States
Received: December 15, 2015
DOI: 10.5430/css.v2n2p23
Accepted: February 10, 2016
Online Published: February 24, 2016
URL: http://dx.doi.org/10.5430/css.v2n2p23
A BSTRACT
Isolated fractures of the anatomic neck of the scapula are extremely rare. To our knowledge, seven such fractures have been
previously reported in the literature with radiographic documentation. We describe another such case and review the anatomy
contributing to deformity in this injury pattern. As with previous cases of this fracture pattern, the plane of the fracture divided the
scapular body from the glenoid fossa, with a short spike of the lateral border of the scapular body attached to the glenoid fragment.
The glenoid fragment demonstrates a unique pattern of inferior displacement and valgus alignment due to the deforming forces
produced by the anatomic structures spanning the fracture. This unstable fracture was fixed through a modified Judet posterior
approach and yielded excellent results.
Key Words: Scapula fracture, Scapula neck fracture, Anatomic neck fracture, Glenoid fracture, Suspensory system, Modified
Judet approach
1. I NTRODUCTION
Scapula fractures account for 1% of all fractures, and isolated fractures of the anatomic neck represent 1% or less
of all scapula fractures, making these injuries extremely
rare.[1] In designing the recently updated AO Foundation and
Orthopaedic Trauma Association (AO/OTA) scapula fracture classification system, Jaeger et al.[1] identified one isolated anatomic neck fracture among 120 consecutive scapula
fractures documented with CT scans and conventional radiographs obtained from 2 centers in Europe and North America.
They designated this fracture 14-F0, defined as a “fracture
of the articular segment, not through the glenoid fossa, but
resulting in the fossa being detached from any part of the
scapula body”. Bartonicek et al. described two such fractures
in 2013 and identified a total of four others in the literature
with radiographic documentation,[2] followed by a related report in 2014 in which they identified one additional anatomic
neck fracture.[3] The purpose of this report is to describe
another such case and review the anatomy contributing to
deformity in this injury pattern.
2. C ASE PRESENTATION
Our patient was a 26-year-old female who was involved in
a motor vehicle collision during January 2014 in which she
sustained an isolated, closed injury to her left (non-dominant)
shoulder, resulting in a displaced fracture of the anatomic
neck of her scapula. Her shoulder was immobilized with a
sling, and she was referred to our trauma center by a community surgeon for a higher level of care several days later.
Physical exam demonstrated a major sulcus sign at rest con-
∗ Correspondence: Drew P Kelly; Email: [email protected]; Address: The University of Oklahoma Health Sciences Center, Department of
Orthopedic Surgery & Rehabilitation, Williams 1380, 920 Stanton L Young Blvd, Oklahoma City, 73104, United States.
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Case Studies in Surgery
sistent with inferior displacement of the humeral head. Radiographs demonstrated a fracture line separating the scapular
body from the glenoid, with a portion of the lateral border
of the scapular body attached to the glenoid fragment (see
Figure 1). The fracture line extended from the coracoglenoid
notch superiorly to the lateral border of the scapular body
3 cm distal to the inferior pole of the glenoid. The glenoid
piece was displaced 2 cm inferiorly with widening of the
subacromial space such that the humeral head was situated
inferior to the level of coracoid. There was widening of the
inferior fracture site resulting in 15-20 degrees of valgus
alignment between the scapular body and the glenoid spike.
2016, Vol. 2, No. 2
anatomically, and two 2.0 mm plates and several 2.4 mm
screws were used for provisional fixation across the fracture
site followed by a lateral buttress plate with multiple lag
screws through the plate. She was admitted for pain control and discharged on postoperative day two. She wore a
sling for two weeks. She began passive range of motion two
weeks after surgery and strengthening exercises six weeks
after surgery. Three month films demonstrated direct healing
in anatomic position (see Figure 2). Full function of the
shoulder was restored.
3. D ISCUSSION
Most operative scapula fractures involve a transverse fracture line caudal to the scapular spine with the caudal segment
displaced laterally, owing to the pull of the infraspinatus,
teres major and minor, and latissimus dorsi (Ada and Miller
type IIC, revised AO/OTA type 14-A3).[4, 5] This is markedly
distinct from fractures of the anatomic neck of the scapula.
With fractures of the anatomic neck of the scapula, the fragment attached to the proximal humerus is formed by the
glenoid fossa and a portion of the lateral border of the scapular body as described by Bartonicek et al.[2] The fracture
runs vertically from the coracoglenoid notch superiorly to
a point along the lateral border of the scapular body that is
2 cm-4 cm distal to the inferior pole of the glenoid. Clinically
these injuries present with a major sulcus sign consistent with
inferior translation of the humeral head, and radiographically
Figure 1. Injury radiographs
Plain films (internal rotation, external rotation, and scapula Y) and the subacromial space is widened with the humeral head
3D reconstructed CT images (anterior, lateral, and posterior) of
positioned inferior to coracoid.
the patient’s scapula at time of injury demonstrate typical
displacement for an anatomic scapular neck fracture: inferior
displacement, valgus rotation of the glenoid fragment in the
coronal plane resulting in an increased glenopolar angle, and
forward rotation of the superior pole of the glenoid in the sagittal
plane.
Lambert et al. describe two intimately related and overlapping lateral scapular suspensory systems: an “inner” one
(lateral clavicle, acromioclavicular ligament, coracoacromial
ligament, coracoid body, coracoclavicular ligaments, and lateral clavicle) and an “outer” one (clavicle, acromioclavicular
joint, scapular spine, lateral scapular angle, coracoclavicular
ligaments, and clavicle).[6] While none of these structures
are damaged in the setting of an anatomic neck fracture,
Arts and Louette suggested this injury represents a floating
shoulder variant.[7] Unlike a fracture of the surgical neck
of the scapula (i.e. medial to the coracoid process), which
may be stabilized by an intact clavicle or coracoclavicular
ligaments, a fracture of the anatomic neck (i.e. lateral to the
coracoid process) will still be relatively unstable even if the
Figure 2. Three-month postoperative films
other structures of the suspensory ring are intact. The only
AP, scapula Y, and axillary lateral views of the patient’s shoulder
osseoligamentous structure attaching the humerus to the sustaken three months after surgery demonstrate direct healing in
anatomic position.
pensory system is the coracohumeral ligament, which may
provide some limit against inferior excursion of the upper
Open reduction internal fixation was performed via modified extremity with gravity. The only attachment between the
Judet posterior approach on the ninth day after her motor glenoid fragment and the proximal scapula is the inferior
vehicle collision. The fracture was cleaned and reduced transverse ligament of the scapula, which connects the spine
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Case Studies in Surgery
of the scapula to the posterosuperior glenoid rim and forms
the dorsal arch through which the suprascapular neurovascular bundle passes on its way to the infraspinatus fossa. This
represents another possible superior tether for the glenoid
fragment as well as a putative site of suprascapular neurovascular bundle compression in the setting of this injury which
has never been described.
The glenohumeral joint capsule and three distinct glenohumeral ligaments (superior, middle, and inferior) attach medially to the periphery of the labrum, bony rim, and anatomic
neck. The inferior glenohumeral ligament, the longest of the
three glenohumeral ligaments, extends towards the surgical
neck of the scapula but blends into the scapular periosteum
within about 10 mm.[8] Since the fracture line generally extends 2 cm-4 cm distal to the inferior pole of the glenoid with
fractures of the anatomic neck of the scapula,[2] the capsular
attachment is entirely contained along the glenoid fragment.
Intraarticular negative pressure created by the intact capsule
is responsible for the continued intimate relationship of the
humeral head and glenoid despite the pull of gravity on the
upper extremity.
In addition to these capsuloligamentous attachments, several
muscles span the fracture plane, namely the deltoid, rotator
cuff, and long heads of the biceps and triceps brachii. The
complete bony lesion at the anatomic neck of the scapula results in an unstable center of rotation for the shoulder, which
allows the characteristic rotational deformity of the glenoid
fragment in several planes. In the coronal plain, the deltoid
overpowers the more inferior muscles and pulls the humerus
along with the glenoid fragment into valgus via the capsular
attachment. In the sagittal plane, the long head of biceps
causes the superior pole of the glenoid to rotate forward, and
the long head of triceps acts with gravity to create inferior
translation of the glenoid fragment through its attachment to
the inferior pole.
This unique injury defies easy radiographic measurements
and well-defined operative criteria alike. According to the
method described by Anavian et al.,[9] the glenopolar angle
measured approximately 55 degrees, and the anterior angulation was 20 degrees in the sagittal plane. There was no
significant sagittal plane translation or glenoid version deviation. As previous authors have pointed out, this injury is
singularly exceptional in that it results in valgus alignment
of the glenoid fragment and an increased glenopolar angle.[2]
Explicit surgical indications in the literature that might apply
to this injury include > 10 mm-20 mm medial/lateral displacement, > 25-45 degrees of angular deformity on a scapular-Y
view, double disruptions of the superior shoulder suspensory
complex with both displaced > 10 mm, glenopolar angle
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2016, Vol. 2, No. 2
< 22 degrees, and open fractures.[5] This fracture meets
none of those criteria but nonetheless represents an unstable pattern unlikely to heal predictably without operative
stabilization due to the deforming forces described above.
We agree with the previous few authors who have published
reports on these rare injuries that open reduction internal fixation is warranted and reliably produces satisfactory clinical
results.
With the exception of bony Bankart lesions, which may be
addressed arthroscopically or through an open deltopectoral
approach,[10] a posterior approach is needed for operative
stabilization of most scapula fractures, including fractures of
the anatomic neck. While a variety of posterior approaches
to the shoulder have been described, we believe that the
modified Judet approach has several advantages over other
exposures for this unique injury. The classic Judet approach
involves making a curvilinear incision overlying the scapular
spine and medial scapular border, elevating the infraspinatus from its fossa, and reflecting the muscle from medial to
lateral on its neurovascular pedicle.[11] The posterior deltoid
can be released from its origin along the scapular spine[12] or
even split to provide further access to the superior and lateral
part of the scapula.[13] A modified Judet approach utilizes a
similar incision to allow access to the internervous interval
between the infraspinatus and teres minor without reflection
of the infraspinatus, which minimizes soft tissue stripping
and risk of injury to the neurovascular pedicle, while still
providing adequate access to the thick bone of the lateral
border of the scapula where the best bone stock for fixation is located.[14] A minimally invasive posterior approach
has been described which uses multiple small incisions to
gain access to the same internervous interval along the thick
borders of the scapula,[15] but limited skin incisions may
prove challenging for surgeons who rarely operate on the
posterior shoulder or in obese patients in whom bony landmarks are obscured. The so-called “two-portal” approach
utilizes the same internervous interval but also mobilizes the
infraspinatus caudally to provide access to superior border of
the scapula between the infraspinatus and supraspinatus,[16]
with the added risk of injury to the suprascapular neurovascular bundle. Partial or complete infraspinatus tenotomy has
been described as another extension of the modified Judet
approach,[13] which avoids risks associated with soft tissue
stripping in the classic Judet approach but carries the obvious drawback of potential tendon healing complications and
risk of rotator cuff dysfunction. Triceps tenotomy has been
shown to improve visualization of the inferior glenoid as
well as allow palpation of the anterior glenoid with the Judet
approach in cadaveric specimens.[17] Authors of the previously limited case reports dealing with surgical treatment of
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Case Studies in Surgery
2016, Vol. 2, No. 2
fractures of the scapular anatomic neck were able to achieve resents the ninth one reported in the literature with accompaanatomic reduction and adequate fixation in all cases without nying radiographs. These are unstable injuries that warrant
performing any tenotomy,[2] as in this case.
operative stabilization. Open reduction internal fixation via
modified Judet approach can produce excellent results as in
In conclusion, fractures of the anatomic neck of the scapula
this case.
are extremely rare injuries that demonstrate a unique pattern of inferior displacement and valgus alignment of the C ONFLICTS OF I NTEREST D ISCLOSURE
glenoid fragment due to the deforming forces produced by The authors declare they have no conflict of interest.
the anatomic structures spanning the fracture. Our case rep-
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